Attach gametest results to PRs

.github/workflows/testreport.yml

@@ -0,0 +1,25 @@
+name: Attach test report
+
+# Needs to be run separately because runs on external repositories can't add checks
+on:
+  workflow_run:
+    workflows: [ "Pull Request Builds" ]
+    types: [ completed ]
+
+jobs:
+  Upload:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download Test Report
+        uses: actions/download-artifact@v4
+        with:
+          name: gametest-results
+          run-id: ${{ github.event.workflow_run.id }}
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Attach Test Report
+        uses: mikepenz/action-junit-report@v3
+        with:
+          commit: ${{github.event.workflow_run.head_sha}}
+          report_paths: 'junit.xml'
+          check_name: Gametest report
+          summary: "Note that most functionality isn't currently tested by Gametest"